Global scientists have warned New Zealand Prime Minister Christopher Luxon that adopting a new biogenic methane target could compromise climate change commitments and have serious implications for its primarily livestock-driven emissions. 

In an open letter addressed to Luxon, the 26 independent scientists argue that the New Zealand government’s new approach to methane lacks scientific backing as it is based on the goal of achieving “no additional warming.”

They say this creates the impression that current high levels of methane emissions are acceptable and, therefore, allowed to continue.

“It redefines the goal of climate action as simply stabilizing the warming impact of emissions from any given source at current levels — rather than seeking to ‘minimize all greenhouse gas emissions’ and their contribution to global warming,” reads the letter.

Current targets aim to slash methane emissions by 10% by 2030 and 24 to 47% by 2050. However, the government is eyeing reductions and reviewing advice from a self-appointed independent scientific panel, which has become a point of contention.

According to reports, Luxon has dismissed the open letter, saying the academics “might want to direct their focus and their letters to other countries” because New Zealand was managing methane more efficiently than “every other country on the planet.”

Signatories include leading academics from Duke University, Victoria University of Wellington, Cornell University, University of Cambridge, University of Oxford, London School of Hygiene and Tropical Medicine, and Chalmers University of Technology.

Livestock emissions under scanner

The International Energy Agency’s global methane tracker indicates methane is responsible for around 30% of the rise in global temperatures since the Industrial Revolution.

Nearly half of New Zealand’s methane emissions come from agriculture, particularly its livestock industry, a major meat and dairy exporter.

However, farming groups like Dairy NZ, Beef + Lamb, and Federated Farmers have opposed current targets, saying the 2050 goals are too high. The “no additional warming” approach is also popular among such lobbies.

“We opposed the current target from day one because we knew there was absolutely no credible science to underpin it. Those figures would require farmers to go much further and faster than is required to stop our contribution to further warming, at a huge economic and social cost to our rural communities,” Federated Farmers president Wayne Langford said in December 2024.

The organization emphasizes that in a lower emissions scenario wher emissions wher global temperature increases are limited to 1.5°C, a 24% methane reduction would prevent farmers from contributing to additional warming.

“It’s incredibly encouraging that the government has taken the step of commissioning this independent review — but we now need them to go one step further and act on its findings,” Langford said at the time.

Meanwhile, environmental groups have called out the government’s “anti-science approach” and support for dairy and meat industries.

“The New Zealand dairy industry is the country’s worst climate polluter. Yet rather than responding to the climate crisis with action, the government is looking to sweep the problem under the rug with creative accounting,” says Greenpeace Aotearoa spokesperson Amanda Larsson.

“Most New Zealanders expect the government to use the best evidence from its appointed experts, not fudging the numbers to let the country’s worst polluters off the hook. This is what happens when you let polluters write the policy.”

Climate equity

The open letter calls on the government to align its targets with recommendations from the country’s independent Climate Change Commission, which recommends more substantial cuts to methane emissions to limit warming to 1.5°C.

The scientists believe that other agriculture-heavy nations might start adopting the “no additional warming” metric, shifting the burden of mitigation to countries with lower agricultural output.

They emphasize that such a move would be inconsistent with Article 4 of the Paris Agreement, which recognizes equity, and that certain nations have a larger responsibility in global efforts to combat climate change due to varying circumstances. It would jeopardize the country’s international commitments, including those under the Global Methane Pledge.